At issue is whether some property owners who have kept rents low over the years can raise them to market rate. Voters last year approved a law extending rent control to owner-occupied buildings of four or fewer units; previously, those apartments had been exempt from rent-hike caps.

In January, the Rent Board passed regulations favoring landlords, giving them a one-time shot at raising rents before the rent-control limits kick in. No increases will be allowed on those units until April 1.

"The bottom line is that Prop. I is law, and we don't want to see anyone try to contradict or subvert it," said June Gutfleisch, Bierman's administrative assistant.

But some property owners, who say the law unfairly burdens landlords who have kept rents low over the years, have indicated that they may take legal action against The City should the Board of Supervisors pass Bierman's legislation.

A public hearing on the issue will be held before a special meeting of the board's Housing and Land Use Committee at 12:30 p.m. Monday. The full board is scheduled to take up the matter at 2 p.m. Both meetings will be held on the fourth floor of the temporary City Hall, 401 Van Ness Ave.&lt;